Such safety ski bindings are known in various designs. In one type of these bindings, the locking mechanism consists of a locking rocker arm which is pivotally supported to the front area of the base member for movement about a pivot axis which extends parallel with respect to transversely extending axle of the sole holder the front area of the locking rocker arm having a locking nose thereon, which in turn cooperates with a counternotch provided at the rear area of the sole holder such that in the downhill skiing position, namely, in the closed position of the binding, the locking nose and the counternotch engage one another; in the release position, be it through an automatic or voluntary release, however, the locking nose and counternotch become disengaged from one another. The locking rocker arm is on its side remote from the locking nose loaded by the locking spring.
In a different known binding of this type, the locking rocker arm is hinged to the upwardly swingable sole holder and is also loaded by a locking spring, whereas the counternotch is provided on the base member.
In another known binding according to French Pat. No. 1 485 708 (see in particular FIGS. 2, 5 and 6), the hand lever is hinged to the spring-loaded locking rocker arm, and the hand lever in the skiing position grips under a ramp on the sole holder by means of its cam-shaped end area and during a voluntary release is supported on a ski-fixed structural part.
All of these structures have the distinct disadvantage that a voluntary stepping out of the binding by means of the hand lever is possible only by overcoming the entire force of the locking spring. This operation can be carried but still relatively simply on a flat terrain, for example during a removal of the skis after skiing; however, on a steep hill, in particular in deep snow or after a fall when the binding, for whichever reasons, did not open, it can be carried out only with extreme difficulties. An injured skier can under these circumstances possibly not at all come free from his skis without the assistance of another person.
It is an object of the invention to substantially reduce the amount of force needed for effecting a voluntary release in a ski binding of the above-mentioned type, without influencing in an unfavorable manner the properly adjusted holding force for the automatic release function.
The set purpose is inventively attained by providing a locking mechanism which loads the sole holder, which has a first locking rocker arm supported on a base member and a second locking rocker arm interposed between the first rocker arm and a locking spring, which second locking rocker arm is also supported on the base member, a hand lever engaging the first locking rocker arm and being supported preferably on the same axle as the first locking rocker arm.
Due to the fact, that the hand lever engages the first locking rocker arm and the locking spring engages the second locking rocker arm, a moment arm is achieved, in which the force which is needed for holding down the sole holder is applied by the locking spring in the desired strength, whereas for the voluntary stepping out of the binding and for overcoming the locking spring, a force which is reduced corresponding with the lever relationships must only be applied onto the hand lever.
In a ski binding according to German OS No. 29 04 798, it is already known to permit the spring force which acts onto a locking rocker arm pivotally suspended from above and through the interpositioning of a cam to act onto the sole holder. The hand lever which effects a voluntary release engages the locking rocker arm, namely, the structural part, loaded by the locking spring. This means, however, that during a voluntary release, the force of the locking spring must be overcome practically totally; only the points of engagement of hand lever and locking spring permit a slight reduction of force.
Compared with this, the invention achieves a particularly favorable force ratio, because the hand lever engages a structural part which is not directly loaded by the locking spring. Thus it is possible to achieve a favorable force ratio or moment arm relationship through the points of engagement and support points of the individual structural parts. Furthermore, in the inventive solution a release function is achieved through a force applied by the hand lever, which feature in the known environment, due to the given construction, could only be realized with great difficulties. A further advantage over the known solution lies also in the provision of two locking rocker arms being able to cooperate with one another without the interpositioning of additional structural parts, which solution in the known design can also not be achieved due to the structural conditions and/or limitations.
Since furthermore in ski bindings the use of each additional structural part increases the susceptibility for breakdown and the weight of the binding, it is of an advantage if additional structural parts, even if to a small degree, can be reduced.
A preferable embodiment of the invention lies in the hand lever being of a bifurcated construction at its region adjacent the first locking rocker arm and having inwardly protruding extensions received in recesses of the first locking rocker arm. The point of engagement of the hand lever on the locking rocker arm can be adjusted through this development corresponding with the respective relationships.
Another preferable embodiment of the invention lies in the first locking rocker arm having an extension on its side facing the second locking rocker arm, which extension lies in a locking recess of the second locking rocker arm. Through this development, a rolling sliding movement is achieved during the release operation without requiring an additional structural part in the form of a roller.
Another preferable embodiment of the invention lies in the first locking rocker arm being connected to the second locking rocker arm through at least one link member pivotally connected by means of bolts to the first and second locking rocker arm. This development improves the precision of the connection of the two locking rocker arms; however, the rolling or pivot friction which now occurs at two points, is also present in this embodiment.